In data storage technology, data replication is the process of copying specified content from a primary storage system to a secondary, or backup, storage system. The secondary storage system can be located on the same site as the primary storage system, but it is often remote from the primary storage system. For example, the primary storage system may be located across country or across the world from the secondary storage system. Data replication is achieved through an initial transfer of the specified data often using standard data migration techniques. After the initial transfer, the backup storage system is kept updated with the primary storage system with any changes that are made to the data in the primary storage system. The backup storage system provides for redundancy and quick recovery of systems in case of a catastrophic failure of the primary storage system.